The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Light detection and ranging (lidar) is a technology that can be used to measure distances to remote targets. Typically, a lidar system includes a light source and an optical receiver. The light source can be, for example, a laser which emits light having a particular operating wavelength. The operating wavelength of a lidar system may lie, for example, in the infrared, visible, or ultraviolet portions of the electromagnetic spectrum. The light source emits light toward a target which then scatters the light. Some of the scattered light is received back at the receiver. The system determines the distance to the target based on one or more characteristics associated with the returned light. For example, the system may determine the distance to the target based on the time of flight of a returned light pulse.
A typical lidar system is configured to wait for the scattered light to return during a certain fixed period of time tmax corresponding to the time it takes a light pulse to travel the maximum distance at which the lidar system is configured to detect targets, and back. For example, the lidar system may be configured to detect objects up to 200 meters away, and tmax accordingly can be approximately 1.33 μs. If the lidar system does not detect scattered light within tmax, the lidar system concludes that no object was present to scatter the outbound pulse, and generates the next light pulse.